It is common for infants to rest or sleep in a sleeping compartment, such as a bassinet, cradle or crib. Typically, the sleeping compartment is fixedly mounted and is intended to a support to remain stationary. However, some sleeping compartments are designed to move while holding an infant during rest, so as to sooth the child.
Some movable sleeping compartments are supported on assemblies that permit a person to push the sleeping compartment to rock the device back-and-forth. Others include a motor to propel the assembly in a swinging or rocking motion. Many prior sleeping compartments, such as bassinets, are constructed to rest on a floor surface and to be located adjacent the floor. Low positioning of sleeping compartments can be inconvenient for a person caring for an infant and may lead to back strain due to the bending and lifting required when placing a child into or removing a child from such sleeping compartments.
Automated rocking assemblies typically utilize a spring to capture some of the kinetic energy while damping the end of an upward stroke of the sleeping compartment and then to return the energy on a downward stroke, and/or they have a motor with a relatively large torque rating, due to the lifting involved in the vertical displacement of the mass (e.g., the sleeping compartment and the infant). However, the large, arcuate motions produced by these prior rocking assemblies are not well suited for gentle, reciprocating propulsion of a sleeping compartment, such as a bassinet.
Some sleeping compartments are designed with a relatively smaller range of motion and are propelled by a motor. These units typically use a series of solenoids or a motor capable of generating relatively high torque at a low speed, as well as resilient members, such as springs, to dampen movements at the end of each stroke of the device. Unfortunately, such components add significant cost and commonly require an AC power source to supply their power requirements.